title: Clinical and pathological features of primary neuroectodermal tumor/Ewing sarcoma of the kidney.
abstract: OBJECTIVE
  To collect and analyze clinical and pathological features of primitive neuroectodermal tumor (PNET)/Ewing sarcoma (EWS), a rare tumor occurring most commonly in bone and soft tissues of young people, which rarely occurs as a primary renal neoplasm and exhibits highly aggressive biological behavior.
  
  
  METHODS
  All cases of PNET/EWS published from 1975 to February 2012 were collected. When available, clinical and pathological data were extracted for each case. Survivals were estimated with the Kaplan-Meier method and compared with the log-rank test with 95% confidence interval (CI).
  
  
  RESULTS
  A total of 116 cases were found. All patients had clinical symptoms as first presentation of disease such as pain (54%), hematuria (29%), and bulky renal mass (28%). Sixty-six percent of patients had stage IV disease at diagnosis. Median disease-free survival (DFS) was 5.0 months (95% CI 2.4-7.6). The probability to be alive at 18 months was 60% and 85% for patients with metastatic disease (M1) or not (M0) at diagnosis, respectively. Median overall survival (OS) was 24 months (95% CI 4.5-15.1) in patients with M1 disease, whereas it was not reached in patients with M0 disease (P <.001). In patients with M0 disease, 50% received neoadjuvant chemotherapy and the 12-month OS was 93% compared to 75% of untreated patients (P = .092). In patients with M1 disease who underwent treatment, the median progression-free survival (PFS) was 22.0 months (95% CI 17.9-26.1) with a clinical benefit in 74% of cases.
  
  
  CONCLUSIONS
  Our findings suggest that PNET/EWS is a rare aggressive tumor affecting principally young people, with a poor prognosis for patients with M1 disease; chemotherapy is an effective strategy in M1 disease and probably also in M0 disease.
authors.affiliation: Department of Radiology, Sapienza University of Rome, Viale Regina Elena, Rome, Italy. emanuela.risi@libero.it
authors.forename: Emanuela
authors.initials: E
authors.lastname: Risi
authors.forename: Roberto
authors.initials: R
authors.lastname: Iacovelli
authors.forename: Amelia
authors.initials: A
authors.lastname: Altavilla
authors.forename: Daniele
authors.initials: D
authors.lastname: Alesini
authors.forename: Antonella
authors.initials: A
authors.lastname: Palazzo
authors.forename: Claudia
authors.initials: C
authors.lastname: Mosillo
authors.forename: Patrizia
authors.initials: P
authors.lastname: Trenta
authors.forename: Enrico
authors.initials: E
authors.lastname: Cortesi
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D018572:Disease-Free Survival; D005260:Female; D006417:Hematuria / Q000209:etiology; D006801:Humans; D053208:Kaplan-Meier Estimate; D007680:Kidney Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D008297:Male; D018396:Mucin-1 / Q000378:metabolism; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D018241:Neuroectodermal Tumors, Primitive, Peripheral / Q000378:metabolism / Q000556:secondary* / Q000628:therapy; D010146:Pain / Q000209:etiology; D016016:Proportional Hazards Models; D051789:Proto-Oncogene Protein c-fli-1 / Q000235:genetics / Q000378:metabolism; D009418:S100 Proteins / Q000378:metabolism; D012512:Sarcoma, Ewing / Q000378:metabolism / Q000556:secondary* / Q000628:therapy; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C078433:FLI1 protein, human; D018396:Mucin-1; D051789:Proto-Oncogene Protein c-fli-1; D009418:S100 Proteins